The present invention relates to a magnetic disk medium, a magnetic disk drive, and a method for detecting the rotational position of a magnetic disk medium, and more particularly to a technique of accurately determining the rotational position of a magnetic disk medium with a low overhead.
Magnetic disk drives write servo data to their magnetic disk media so as to be able to servo-control their heads. One technique for writing servo data is the sector servo system in which servo data is written to each sector, or data region, which is a subdivision of a track on a magnetic disk medium. Each piece of servo data includes a track number and a sector number.
Conventionally, the rotational position of a magnetic disk medium is determined based on a sector number read by the head.